Organization and Plan of Business Operations	6 Months Ended
Jun. 30, 2025
Organization and Plan of Business Operations [Abstract]
Organization and Plan of Business Operations	Note 1 — Organization and Plan of Business Operations M3-Brigade Acquisition VI Corp. (the “Company”) is a newly incorporated blank check company incorporated as a Cayman Islands exempted corporation on June 5, 2025. The Company was incorporated for the purpose of effecting a merger, share exchange, asset acquisition, share purchase, reorganization or similar Business Combination with one or more businesses (the “Business Combination”). The Company has not selected any specific Business Combination target and the Company has not, nor has anyone on its behalf, engaged in any substantive discussions, directly or indirectly, with any Business Combination target with respect to an initial Business Combination with the Company. As of June 30, 2025, the Company had not commenced any operations. All activity for the period from June 5, 2025 (inception) through June 30, 2025 relates to the Company’s formation and the initial public offering (the “Initial Public Offering”), which is described below. The Company will not generate any operating revenues until after the completion of its initial Business Combination, at the earliest. The Company will generate non-operating income in the form of interest income from the investment of the proceeds derived from the Initial Public Offering. The Company has selected December 31 as its fiscal year end. The registration statement for the Company’s Initial Public Offering was declared effective on August 26, 2025. On August 28, 2025, the Company consummated the Initial Public Offering of 34,500,000 units (the “Units” and, with respect to the Class A ordinary shares included in the Units being offered, the “Public Shares”), which includes the full exercise by the underwriters of their over-allotment option in the amount of 4,500,000 Units, at $10.00 per Unit, generating gross proceeds of $345,000,000. Each Unit consists of one Class A ordinary share and one-third of one redeemable warrant (each, a “Public Warrant”). Simultaneously with the closing of the Initial Public Offering, the Company consummated the sale of 5,333,333 warrants (the “Private Placement Warrants” and together with the Public Warrants, the “Warrants”) at a price of $1.50 per Private Placement Warrant, in a private placement to the Company’s sponsor, M3-Brigade Sponsor VI LLC, a Delaware limited liability company (the “Sponsor”), and Cantor Fitzgerald & Co. (“Cantor”), the representative of the underwriters, generating gross proceeds of $8,000,000. Each whole Warrant entitles the holder to purchase one Class A ordinary share at a price of $11.50 per share, subject to adjustment. Of those 5,333,333 Private Placement Warrants, the Sponsor purchased 4,333,333 Private Placement Warrants and Cantor purchased 1,000,000 Private Placement Warrants. Transaction costs amounted to $23,148,834, consisting of $6,000,000 of cash underwriting fee, $16,425,000 of deferred underwriting fee, and $723,834 of other offering costs. The Company’s management has broad discretion with respect to the specific application of the net proceeds of the Initial Public Offering and the Private Placement Warrants, although substantially all of the net proceeds are intended to be generally applied toward consummating a Business Combination (less deferred underwriting commissions). The Company’s Business Combination must be with one or more target businesses that together have a fair market value equal to at least 80% of the net balance in the Trust Account (as defined below) (excluding the amount of deferred underwriting discounts held and taxes payable on the interest earned on the Trust Account) at the time of the signing an agreement to enter into a Business Combination. However, the Company will only complete a Business Combination if the post-Business Combination company owns or acquires 50% or more of the outstanding voting securities of the target or otherwise acquires a controlling interest in the target sufficient for it not to be required to register as an investment company under the Investment Company Act of 1940, as amended (the “Investment Company Act”). There is no assurance that the Company will be able to successfully effect a Business Combination. Following the closing of the Initial Public Offering, on August 28, 2025, an amount of $345,000,000 ($10.00 per Unit) from the net proceeds of the sale of the Units and the Private Placement Warrants was placed in the trust account (the “Trust Account”), located in the United States, with Continental Stock Transfer & Trust Company acting as trustee, and may only be held as cash or invested in (i) U.S. government treasury obligations with a maturity of 185 days or less or in money market funds meeting certain conditions under Rule 2a-7 under the Investment Company Act, which invest only in direct U.S. government treasury obligations or (ii) an interest bearing bank demand deposit account or other accounts at a bank. Except with respect to interest earned on the funds held in the Trust Account that may be released to the Company to pay its taxes, if any, the proceeds from the Initial Public Offering and the sale of the Private Placement Warrants will not be released from the Trust Account until the earliest of (i) the completion of the Company’s initial Business Combination, (ii) the redemption of the Company’s public shares if the Company is unable to complete the initial Business Combination within 24 months from the closing of the Initial Public Offering or by such earlier liquidation date as the board of directors may approve (the “Completion Window”), subject to applicable law, or (iii) the redemption of the Company’s public shares properly submitted in connection with a shareholder vote to amend the Company’s amended and restated memorandum and articles of association to (A) modify the substance or timing of the Company’s obligation to allow redemption in connection with the initial Business Combination or to redeem 100% of the Company’s public shares if the Company has not consummated an initial Business Combination within the Completion Window or (B) with respect to any other material provisions relating to shareholders’ rights or pre-initial Business Combination activity. The proceeds deposited in the Trust Account could become subject to the claims of the Company’s creditors, if any, which could have priority over the claims of the Company’s public shareholders. The Company will provide the Company’s public shareholders with the opportunity to redeem all or a portion of their public shares upon the completion of the initial Business Combination either (i) in connection with a general meeting called to approve the initial Business Combination or (ii) without a shareholder vote by means of a tender offer. The decision as to whether the Company will seek shareholder approval of a proposed initial Business Combination or conduct a tender offer will be made by the Company, solely in its discretion. The public shareholders will be entitled to redeem their shares at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account calculated as of two business days prior to the consummation of the initial Business Combination, including interest earned on the funds held in the Trust Account (less taxes payable), divided by the number of then outstanding public shares, subject to the limitations. The amount in the Trust Account is initially invested at $10.00 per public share. The ordinary shares subject to redemption were recorded at a redemption value and classified as temporary equity upon the completion of the Initial Public Offering, in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 480, “Distinguishing Liabilities from Equity.” The Company will have only the duration of the Completion Window to complete the initial Business Combination. If the Company is unable to complete its initial Business Combination within the Completion Window, the Company will cease all operations except for the purpose of winding up and, as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest earned on the funds held in the Trust Account (less taxes payable and up to $100,000 of interest to pay dissolution expenses), divided by the number of then outstanding public shares, which redemption will constitute full and complete payment for the public shares and completely extinguish public shareholders’ rights as shareholders (including the right to receive further liquidation or other distributions, if any), subject to the Company’s obligations under Cayman Islands law to provide for claims of creditors and subject to the other requirements of applicable law. The Sponsor, officers and directors have entered into a letter agreement with the Company, pursuant to which they have agreed to (i) waive their redemption rights with respect to their founder shares and public shares in connection with the completion of the initial Business Combination; (ii) waive their redemption rights with respect to their founder shares and public shares in connection with a shareholder vote to approve an amendment to the Company’s amended and restated memorandum and articles of association (A) to modify the substance or timing of the Company’s obligation to allow redemption in connection with the initial Business Combination or to redeem 100% of the public shares if the Company has not consummated an initial Business Combination within the Completion Window or (B) with respect to any other material provisions relating to shareholders’ rights or pre-initial Business Combination activity; (iii) waive their rights to liquidating distributions from the Trust Account with respect to their founder shares if the Company fails to complete the initial Business Combination within the Completion Window, although they will be entitled to liquidating distributions from the Trust Account with respect to any public shares they hold if the Company fails to complete the initial Business Combination within the Completion Window and to liquidating distributions from assets outside the Trust Account; and (iv) vote any founder shares held by them and any public shares purchased during or after the Initial Public Offering (including in open market and privately negotiated transactions) in favor of the initial Business Combination. The Company’s Sponsor has agreed that it will be liable to the Company if and to the extent any claims by a third party for services rendered or products sold to the Company (except for the Company’s independent auditors), or a prospective target business with which the Company has entered into a written letter of intent, confidentiality or other similar agreement or Business Combination agreement (except for the Company’s independent auditors), reduce the amount of funds in the Trust Account to below the lesser of (i) $10.00 per public share and (ii) the actual amount per public share held in the Trust Account as of the date of the liquidation of the Trust Account, if less than $10.00 per share due to reductions in the value of the trust assets, less taxes payable, provided that such liability will not apply to any claims by a third party or prospective target business who executed a waiver of any and all rights to the monies held in the Trust Account (whether or not such waiver is enforceable) nor will it apply to any claims under the Company’s indemnity of the underwriters of the Initial Public Offering against certain liabilities, including liabilities under the Securities Act of 1933, as amended (the “Securities Act”). However, the Company has not asked the Sponsor to reserve for such indemnification obligations, nor has the Company independently verified whether the Sponsor has sufficient funds to satisfy its indemnity obligations and the Company believes that the Sponsor’s only assets are securities of the Company. Therefore, the Company cannot assure that the Sponsor would be able to satisfy those obligations.

Organization and Plan of Business Operations

6 Months Ended

Jun. 30, 2025

Organization and Plan of Business Operations [Abstract]

Organization and Plan of Business Operations

Note 1 — Organization and Plan of Business Operations

M3-Brigade Acquisition VI Corp. (the “Company”) is a newly incorporated blank check company incorporated as a Cayman Islands exempted corporation on June 5, 2025. The Company was incorporated for the purpose of effecting a merger, share exchange, asset acquisition, share purchase, reorganization or similar Business Combination with one or more businesses (the “Business Combination”). The Company has not selected any specific Business Combination target and the Company has not, nor has anyone on its behalf, engaged in any substantive discussions, directly or indirectly, with any Business Combination target with respect to an initial Business Combination with the Company.

As of June 30, 2025, the Company had not commenced any operations. All activity for the period from June 5, 2025 (inception) through June 30, 2025 relates to the Company’s formation and the initial public offering (the “Initial Public Offering”), which is described below. The Company will not generate any operating revenues until after the completion of its initial Business Combination, at the earliest. The Company will generate non-operating income in the form of interest income from the investment of the proceeds derived from the Initial Public Offering. The Company has selected December 31 as its fiscal year end.

The registration statement for the Company’s Initial Public Offering was declared effective on August 26, 2025. On August 28, 2025, the Company consummated the Initial Public Offering of 34,500,000 units (the “Units” and, with respect to the Class A ordinary shares included in the Units being offered, the “Public Shares”), which includes the full exercise by the underwriters of their over-allotment option in the amount of 4,500,000 Units, at $10.00 per Unit, generating gross proceeds of $345,000,000. Each Unit consists of one Class A ordinary share and one-third of one redeemable warrant (each, a “Public Warrant”).

Simultaneously with the closing of the Initial Public Offering, the Company consummated the sale of 5,333,333 warrants (the “Private Placement Warrants” and together with the Public Warrants, the “Warrants”) at a price of $1.50 per Private Placement Warrant, in a private placement to the Company’s sponsor, M3-Brigade Sponsor VI LLC, a Delaware limited liability company (the “Sponsor”), and Cantor Fitzgerald & Co. (“Cantor”), the representative of the underwriters, generating gross proceeds of $8,000,000. Each whole Warrant entitles the holder to purchase one Class A ordinary share at a price of $11.50 per share, subject to adjustment. Of those 5,333,333 Private Placement Warrants, the Sponsor purchased 4,333,333 Private Placement Warrants and Cantor purchased 1,000,000 Private Placement Warrants.

Transaction costs amounted to $23,148,834, consisting of $6,000,000 of cash underwriting fee, $16,425,000 of deferred underwriting fee, and $723,834 of other offering costs.

The Company’s management has broad discretion with respect to the specific application of the net proceeds of the Initial Public Offering and the Private Placement Warrants, although substantially all of the net proceeds are intended to be generally applied toward consummating a Business Combination (less deferred underwriting commissions).

The Company’s Business Combination must be with one or more target businesses that together have a fair market value equal to at least 80% of the net balance in the Trust Account (as defined below) (excluding the amount of deferred underwriting discounts held and taxes payable on the interest earned on the Trust Account) at the time of the signing an agreement to enter into a Business Combination. However, the Company will only complete a Business Combination if the post-Business Combination company owns or acquires 50% or more of the outstanding voting securities of the target or otherwise acquires a controlling interest in the target sufficient for it not to be required to register as an investment company under the Investment Company Act of 1940, as amended (the “Investment Company Act”). There is no assurance that the Company will be able to successfully effect a Business Combination.

Following the closing of the Initial Public Offering, on August 28, 2025, an amount of $345,000,000 ($10.00 per Unit) from the net proceeds of the sale of the Units and the Private Placement Warrants was placed in the trust account (the “Trust Account”), located in the United States, with Continental Stock Transfer & Trust Company acting as trustee, and may only be held as cash or invested in (i) U.S. government treasury obligations with a maturity of 185 days or less or in money market funds meeting certain conditions under Rule 2a-7 under the Investment Company Act, which invest only in direct U.S. government treasury obligations or (ii) an interest bearing bank demand deposit account or other accounts at a bank. Except with respect to interest earned on the funds held in the Trust Account that may be released to the Company to pay its taxes, if any, the proceeds from the Initial Public Offering and the sale of the Private Placement Warrants will not be released from the Trust Account until the earliest of (i) the completion of the Company’s initial Business Combination, (ii) the redemption of the Company’s public shares if the Company is unable to complete the initial Business Combination within 24 months from the closing of the Initial Public Offering or by such earlier liquidation date as the board of directors may approve (the “Completion Window”), subject to applicable law, or (iii) the redemption of the Company’s public shares properly submitted in connection with a shareholder vote to amend the Company’s amended and restated memorandum and articles of association to (A) modify the substance or timing of the Company’s obligation to allow redemption in connection with the initial Business Combination or to redeem 100% of the Company’s public shares if the Company has not consummated an initial Business Combination within the Completion Window or (B) with respect to any other material provisions relating to shareholders’ rights or pre-initial Business Combination activity. The proceeds deposited in the Trust Account could become subject to the claims of the Company’s creditors, if any, which could have priority over the claims of the Company’s public shareholders.

The Company will provide the Company’s public shareholders with the opportunity to redeem all or a portion of their public shares upon the completion of the initial Business Combination either (i) in connection with a general meeting called to approve the initial Business Combination or (ii) without a shareholder vote by means of a tender offer. The decision as to whether the Company will seek shareholder approval of a proposed initial Business Combination or conduct a tender offer will be made by the Company, solely in its discretion. The public shareholders will be entitled to redeem their shares at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account calculated as of two business days prior to the consummation of the initial Business Combination, including interest earned on the funds held in the Trust Account (less taxes payable), divided by the number of then outstanding public shares, subject to the limitations. The amount in the Trust Account is initially invested at $10.00 per public share.

The ordinary shares subject to redemption were recorded at a redemption value and classified as temporary equity upon the completion of the Initial Public Offering, in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 480, “Distinguishing Liabilities from Equity.”

The Company will have only the duration of the Completion Window to complete the initial Business Combination. If the Company is unable to complete its initial Business Combination within the Completion Window, the Company will cease all operations except for the purpose of winding up and, as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest earned on the funds held in the Trust Account (less taxes payable and up to $100,000 of interest to pay dissolution expenses), divided by the number of then outstanding public shares, which redemption will constitute full and complete payment for the public shares and completely extinguish public shareholders’ rights as shareholders (including the right to receive further liquidation or other distributions, if any), subject to the Company’s obligations under Cayman Islands law to provide for claims of creditors and subject to the other requirements of applicable law.

The Sponsor, officers and directors have entered into a letter agreement with the Company, pursuant to which they have agreed to (i) waive their redemption rights with respect to their founder shares and public shares in connection with the completion of the initial Business Combination; (ii) waive their redemption rights with respect to their founder shares and public shares in connection with a shareholder vote to approve an amendment to the Company’s amended and restated memorandum and articles of association (A) to modify the substance or timing of the Company’s obligation to allow redemption in connection with the initial Business Combination or to redeem 100% of the public shares if the Company has not consummated an initial Business Combination within the Completion Window or (B) with respect to any other material provisions relating to shareholders’ rights or pre-initial Business Combination activity; (iii) waive their rights to liquidating distributions from the Trust Account with respect to their founder shares if the Company fails to complete the initial Business Combination within the Completion Window, although they will be entitled to liquidating distributions from the Trust Account with respect to any public shares they hold if the Company fails to complete the initial Business Combination within the Completion Window and to liquidating distributions from assets outside the Trust Account; and (iv) vote any founder shares held by them and any public shares purchased during or after the Initial Public Offering (including in open market and privately negotiated transactions) in favor of the initial Business Combination.

The Company’s Sponsor has agreed that it will be liable to the Company if and to the extent any claims by a third party for services rendered or products sold to the Company (except for the Company’s independent auditors), or a prospective target business with which the Company has entered into a written letter of intent, confidentiality or other similar agreement or Business Combination agreement (except for the Company’s independent auditors), reduce the amount of funds in the Trust Account to below the lesser of (i) $10.00 per public share and (ii) the actual amount per public share held in the Trust Account as of the date of the liquidation of the Trust Account, if less than $10.00 per share due to reductions in the value of the trust assets, less taxes payable, provided that such liability will not apply to any claims by a third party or prospective target business who executed a waiver of any and all rights to the monies held in the Trust Account (whether or not such waiver is enforceable) nor will it apply to any claims under the Company’s indemnity of the underwriters of the Initial Public Offering against certain liabilities, including liabilities under the Securities Act of 1933, as amended (the “Securities Act”). However, the Company has not asked the Sponsor to reserve for such indemnification obligations, nor has the Company independently verified whether the Sponsor has sufficient funds to satisfy its indemnity obligations and the Company believes that the Sponsor’s only assets are securities of the Company. Therefore, the Company cannot assure that the Sponsor would be able to satisfy those obligations.